The purchase of a mass spectrometer to be used for the obtaining of spectra of biomedically important organic synthetic intermediates and products will provide research data for the following NIH project categories currently in progress at the Chemistry Department of the University of Pittsbugh: 1) Chemical synthesis of biologically active agents such as antibiotics (pseudomonic acids, rubradirins, polymixin B, chuangxinmycin), antitumor agents (jatrophatrione, bactobolin), cell enzyme agents (Vitamin B12, methyl malyonyl coenzyme A), and important natural products (mitosene, rugulovasines, guaiazulene, chamazulene, (plus and minus)-Beta-methyleneaspartic acid, etc.). 2) Structure and molecular weight determination for a wide variety of enzymes, drugs, and natural products. Additional projects which will utilize the mass spectrometer include comparison studies of fast atom bombardment and esorption chemical ionization with laser desorption ionization and conventional electron impact ionization.